End liner for grinding mills



iii-tug. 30, 1938. s, M 2,128,468

END LINER FOR GRINDING MILLS Filed Sept. 9, 1955 2 Sheets-Sheet i 3 1N VENTOR.

2 Swen 5L. MALE/e 6 V; iE A ORNEY.

Aug. 30, 1938. s. L. MILLER END LINER FOR GRINDING MILLS Filed Sept. 9, 1955 2 Sheets-Sheet 2 I R m N E V m -57HPKSL. MILLEE.

ATTORNEY.

Patented Aug. 30, 1938 UNITED STATES FATE NT OF F I QE Starks L. Miller, Denver, 0010., assignor to American Ball-Mill Company, Denver, 0010.

Application September 9, 1935, Serial No. 39,762

3 Claims.

This invention relates to improvements in grinding mills of the type employed in grinding ores and the like, which employ attrition bodies such as balls or rods. The invention relates more particularly to the construction of the end liners and the means for securing them in place.

The principal object of this invention is to provide sectional end liners, throat rings and ballretainers that are individually removable without disturbing the other sections.

Anotherobject is to provide a simple means for holding the sections in place and which can be readily released for the purpose of permitting the removal of the sections.

A further object is to provide means for securing sectional end liners, ball-retainers and throat rings in place in a grinding mill by the employment of radially acting forces.

The above and other objects that may appear as the description proceeds are obtained by means of a construction and an arrangement of parts that will now be described in detail and for this purpose reference will be had to the accompanying drawings in which the invention has been illustrated, and in which Figure 1 is a view, partly in section and partly in side elevation, showing a grinding mill constructed in accordance with this invention;

Figure 2 is a section taken on line'2'2, Figure 1, looking toward the discharge end of the mill;

Figure 3 is a section taken on line 3-3, Figure 1, looking toward the'intake trunnion or the-feed end of the mill;

Figure 4 is a View, partly in section'and partly in elevation, looking in the direction of arrow 4',

Figure 5;

Figure 5 is a section taken on line 5-'5, Figure 4;

Figure 6 is .a section taken. on line 6--6, Figure'5;

Figure 7 is a section taken on line 'l'l; Figure 5;

Figure 8 is a section taken online 88, Figure 9;

Figure 9 is a section taken online 99, Fig ure 8;

Figure 10 is a section taken on line I il-lli, Figure 9;

Figure 11 is a section, taken on line 'lZ-IZ, Figure 12;

Figure 12 is a section, taken on line H-Ii, Figure 11;

Figure 13 is a section taken on line I3l3, Figure 11.

In the drawings reference numeral 5 designates the shell, numerals 6 and l the heads at the intake and the discharge end respectively, and numerals 8 and 9 designate respectively the intake and the discharge trunnions. The trunnions are mounted for rotation in bearings Ill 5 carried on suitable supports ll. Located within the shell are a number of channelled girders I2, arranged in spaced parallel relation with the web toward the inside and the edges of the flanges in contact with the shell. Liner sections l3 are 1| supported on the girders and held in assembled and spaced relation by means of curved wedges l4.

Since the invention here relates more particularly to the construction of and the method of securing the end liners, throat ring and discharge grate in place the construction of the side liners will not be further described.

Referring now more particularly to Figures 1, 2 and 3, it will be seen that abutments I5 are secured to the inner surfaces of the heads. The abutments may be rings, which are secured in place by welding or by bolts or rivets, or they may be formed from a number of separate sections secured in place by similar means.

It will be observed that the inside edges of the L abutments are beveled so as to provide an undercut surface, as shown most clearly in Figure 9.

At the inner end of the intake or feed trunnion 8 a sectional throat ring is provided, which con sists of a plurality of sections 16. In 'theexample illustrated the throat ring is formed from four sectors each of 90 angular extent. The outer surface of each sector i6 is provided with an outwardly facing beveled shoulder which is so positioned that it will engage the inside of the abutments in the manner shown most clearly in Figure 9.

The radial surfaces of the sectors [6 are provided with curved tapering grooves for the reception of curved wedges l8 whose wider ends are toward the inside as shown most clearly in Figure 8. The sectors l6 are of such size that theycan be put into position and then moved radially until the shoulders I? engage the cooperating beveled shoulders of the abutments. After the blocks or sectors l6 are properly positioned, the wedges l8 are inserted and driven home until the pressure of the shoulders I! against the abutments is sufiicient to hold the sectors in place.

At the inner end of the discharge trunnion 9 a sectional ball-retainer is positioned and held in place by means substantially identical with that employed with the throat ring. The ballretainer has been shown as comprising four sector-shaped parts IQ of a transverse section-like that illustrated in Figure 5. Each part I9 has an outwardly directed shoulder I! while adjacent radial sides have curved tapered grooves for the reception of the wedges I8.

From Figures 1, 2 and 3 it will be seen that the inside of the discharge head I is provided with a plurality of truncated triangle-shaped liner sections 24, whose shape and the manner of securing them in place is most clearly shown in Figures 4 and 5. It will be seen from Figure 4 that the end liner sections are so positioned that the sides lie in radii bisecting the girders I2 and that their bases are therefore formed from two short straight sections b and 0.

An elongated wedge 25 is secured transversely of each girder and serves as an abutment for the straight end walls b and c of adjacent sections 24. The opposing sides of adjacent sections are provided with tapering arcuate grooves for the reception of the curved tapering wedges I8.

In order to enhance the holding function of keys I8 throughout the maximum period of wear on the liner sections 24, the heads 5 and I are provided with pockets 38 as illustrated in Figures 5, '7, 9 and 10. The liner sections 24, 23a and 2% have flanges 3|, 3Ia and 3Ib respectively which extend into the pockets 30 when the keys I8 are driven into the grooves.

It will be noted in Figure 5 that the keys I8 extend through the grooves to a greater depth than the normal thickness of the liner sections 24, indicated by the dotted line.

From the foregoing, it will be apparent that no matter how thin the end liners wear, there will be enough of the key IS in the grooves within the flanges 3i to prevent the sections from separating.

When the sections are positioned as shown in Figure 4, and separated by the wedges, the end walls I) and will be forced radially against the wedges 25 and the end liners will thus be securely held in place without the use of bolts; the wedge 25 having its inner edges so beveled as to undercut the adjacent liner. When an end liner section is to be removed a wedge at one side is driven out after which the wedge on the opposite side can readily be removed, thereby completely releasing the section.

The liners on the inside of head 6 are somewhat differently formed and are held in place by specificially different means, all as will now be described.

The liners of head 6 are each formed from two parts 24a and 2%, which together equal one liner 24. The abutment or abutnients Ida have both the inner and outer edges beveled, in the manner shown in Figure 9, and the girders have wedges 25 secured thereto the same as in Figure 4. The bottom side of section 24a and the top of section 24b are provided with cooperating curved tapering grooves for the reception of a curved wedge I8 which serves to force the inner end of section 24a against the outer edge of the abutments [a and the outer end of section 241) against the wedge 25.

In Figures 11, 12 and 13 another way of securing the liners in position has been shown. The abutment I5a has been illustrated as a ring having both its inner and its outer edges beveled.

- This ring is secured to the head in any suitable way and instead of being a continuous ring as shown, may be formed from a plurality of segments.

Instead of the wedges shown in Figure 9 a curved or segmental shaped lug 26 is attached to each girder near its end, the base of each liner section 24d is provided with a curved tapering groove for the reception of a correspondingly curved tapered wedge I8b which is positioned between the lug 26 and the inside of the head. The wedge I8b is somewhat conical, and the groove in section 2401 is similarly inclined with the result that when the wedge is driven home the resultant force will be along line 0-band tends to force the sections against the inside of the head.

It will be seen from the above description that the parts are held in place by a radial force which acts to expand the throat ring, the grate and the end liners, radially against abutments having beveled edges, which abutments have been indicated by numeral I5.

The curved wedges employed for holding the end liners in place have been designated throughout the several views by numeral I8 as they are all alike except as to size.

Throughout the claims the words liners and liner sections will be employed in a sense broad enough to include the throat ring and grate sections as well as the other liner sections, as the several kinds of liners are all secured in place in the same way.

Attention has previously been called to the fact that the abutments may be rings or a plurality of separate sections arranged in the form of a circle and therefore whenever the expression annular abutment or ring abutment is used, it is to be understood as including the equivalent thereof.

Having described the invention, what is claimed as new is:

1. In a grinding mill, a shell, a head at an end thereof, an abutment on the head, the abutment having an undercut shoulder, a girder on the shell, a lug on the girder spaced from an end thereof, a liner positioned between the girder and the abutment, the liner having a beveled shoulder for engaging the undercut shoulder on the abutment, there being a groove in the liner, and a spreader positioned in the groove and engaging the girder between the lug and the head for producing a force urging the shoulders into engagement.

2. A grinding mill having a shell, a head at an end thereof, the head having a trunnion, liners for the head, comprising a central portion formed from several parts, each part having a portion extending into the trunnion and another portion projecting over the surface of the head immediately surrounding the trunnion, an abutment 1 von the head adjacent the trunnion, having its inner edge undercut, the liners having outwardly facing shoulders inclined to fit the shoulder on the abutment, means for expandingthe liner assembly to force the shoulders thereof into interlocking engagement with the shoulder on the abutment, a second abutment means positioned adjacent the periphery of the head, the inner edge of the outer abutment means being undercut, a plurality of liners positioned between the two abutments and provided with outwardly directed shoulders shaped to engage the undercut shoulder on the last-mentioned abutment, and means for expanding the liner assembly to secure interlocking engagement between the shoulders.

3. A grinding mill having a substantially cylindrical shell, a head for closing one end thereof, the head having a tubular trunnion, liners for the inside of the head, the liner comprising a central portion formed from several sector-shaped parts, each part having a portion extending into the trunnion and another portion projecting over the surface of the head immediately surrounding the trunnion, an annular abutment attached to the inner surface of the head in concentric arrangement with the trunnion, the abutment having both its inner and its outer edges beveled and undercut, the liners having outwardly facing shoulders inclined to fit the shoulder on the inside of the abutment, means for expanding the liners to increase its diameter and force the shoulders thereof into interlocking engagement with the inner shoulder on the abutment, a second abutment means positioned adjacent the periphery of the head and spaced from the first abutment, the inner edge of the outer abutment means being beveled and undercut, a plurality of twopart, truncated, sector-shaped liners located in the annular area between the abutments, each part of the liners having a shoulder facing the undercut shoulder of the adjacent abutment and wedge means interposed between the two parts of each liner for expanding the annular liner assembly radially to secure engagement between the shoulders of the abutment and the shoulders of the liners.

STARKS L. MILLER. 

